Refrigerator cooling system design

ABSTRACT

A refrigerator is provided where the cold air for refrigerating the fresh food space is force-circulated over a portion of the wall surface of this food compartment. This wall surface also serves as a wall for the freezer compartment of the refrigerator so that there is heat removal from the fresh food space through the food compartment wall. A portion of the time the fresh food side of this wall is maintained at above 32* so that water will condense thereon and run by gravity to a convenient point for disposal. A circulating fan within the fresh food space is used so that moisture does not condense on the containers and shelves therein with a resultant dripping of moisture on the food stored at lower levels of the food storage space. A single evaporator cooler is provided and this is contained in the frozen food space of the refrigerator, with a fan also provided in this space for circulating air within the frozen food space. To ensure that the wall between the frozen food space and the fresh food space is sometimes above 32* F., the fan in the fresh food space is in active circulating condition at all times when the refrigerator compressor and the fan for the frozen space are not operating.

provided where the cold air for pace is force-circulated over a wallsurface of this food compartment. This wall ll for the freezercompartment of re is heat removal from the fresh d compartment wall. Aportion of esh food side of this wall is maintained at above ter willcondense thereon and run by gravity to a an within the 0 that moisturedoes not condense on Inventor John A. McLean Primary ExaminerWilliam J.W

Columbus, Ohio Attorneys-F. H. Henson, E. C. Arenz and R. B. Farley28,676 Apr. 15, 1970 J 11, 1972 ABSTRACT: A refrigerator is WestinghouseElectric Corporation refrigerating the fresh food 5 Pittsburgh, Pa.Portion of the surface also serves as a wa the refrigerator so that theSYSTEM DESIGN food space through the foo 8 Claims, 3 Drawing Figs. thetime the fr 32 so that wa [52] U.S. convenient p for diSposaL Acirculating f fresh food space IS used s United States Patent [21]AppLNo.

[22] Filed [45] Patented [73] Assignee [54] REFRIGERATOR COOLING e nndee aeoh h aof t t Ofn f .l FlO wus m h .l .B n m m m m m m W m mmmmm mmmfl fl n mm o g s a e ie u rsnm ae r dv wmro 2 3 lPe b e W hhl wm. n awm T .mWHOMW KO d n mmmummcnmm r ai nm m em erO h ce vo da lt o iCSTOPCOPYD- h O Sf w fO S S dmt. 0a ho o d hn e 1 m m m m me flmo r rtfle e e h e 1 nn 6. .mofltm wm me n mM s n Pa LB u. n m ewp enm .mc dcCOWi OWn mmsmmcmsc manu 1 z 7 0 6 066 0 8 888 111 222 II d68 666 4 s .l.2 3 F Sm m m m m m m m u n n T" H 1 eA u I u m C mnm /\J m u E m m m B mcT mm 0 2 I u m m w n" t Vvl :2 u" e m." fimcs Q Tm 801 I M N555 me "s f203 o 11 d and 333 n 266 [F 1 no 11 Mm, 6 .55 ll H 222 PATENTED JAN! 11972 SHEET 1 (IF 2 FIG. 2

l l ll l/ 1 I! ll l 1/ 1/ 1/ 11' INVENTOR John A. McLean mfl/lflATTORNEY REFRIGERATOR COOLING SYSTEM DESIGN BACKGROUND OF THEINVENTION 1. Field of the Invention This invention relates to a systemfor cooling refrigerated spaces and, more specifically, relates to asystem for cooling a frozen food space and fresh food storage space bythe use of a single evaporative cooler.

2. Description of the Prior Art In single-evaporator, forced-convection,two-temperature refrigerators, it has been the general practice tocirculate the major portion of the air through the evaporator coil andfreezer compartment. A small portion of the refrigerated air was thenalso directed through the fresh food storage space to providerefrigeration for it and to pick up excess moisture and carry the heatand moisture to the evaporator coil. Such arrangements have resulted inan excessive drying of exposed food in the fresh food storagecompartment and an excessive number of times in which the defrostarrangement for the refrigerator had to be activated.

A known improvement over this arrangement for refrigeration has beendeveloped by others where the cold air for refrigerating the fresh foodspace is circulated over some portion of the outside surface of thisfood compartment. This provides for heat removal from the fresh foodspace through the food compartment wall. By various arrangements therefrigerated part of the food compartment wall is intended to bemaintained at above 32 F. for at least a portion of the time so thatwater which is condensed on this part of the wall may run by gravity toa convenient point for disposal. Unless a circulating fan within thefresh food space is used, it has been found that this type of systempermits too much moisture to condense on containers and shelves with aresultant dripping into foods stored at the lower levels of the freshfood space. Further, even with the addition of such a circulating fan, arather complicated control system had to be provided to insure that therefrigerated portion of the compartment wall had a temperature of above32 F. for a portion of the refrigeration cycle so that proper drainageof moisture could be obtained. Accordingly, it would be advantageous toprovide a singleevaporator, forced-convection, two-temperaturerefrigerator with a circulating fan in the fresh food space and with acon trol system incorporating this circulating fan into the overallrefrigeration system to ensure that the wall disposed between the frozenspace and the fresh food space was maintained, for at least a portion ofthe time, above the critical freezing temperature of 32 F.

SUMMARY OF THE INVENTION The instant invention is particularlyapplicable to a side-byside type of refrigerator where a large area ofvertical insulated wall divides the frozen food and fresh food spaces.The frozen food space is cooled by an evaporator coil which may beplaced against the rear wall of the freezer compartment. A fandistributes air through this evaporator coil and the frozen food space,with a substantial portion of this air being passed through an air ductformed against the wall dividing the fresh and frozen food spaces.Because of the high velocity of air maintained in this duct duringfrozen food fan operation, a high coefficient of surface heat transferwill occur to provide the fresh food space with a large amount ofrefrigeration. This frozen food fan is arranged to operate when thecompressor of the refrigerating system is operating and to be off whenthe compressor is no longer operating so that the surface coefficient ofheat transfer at this side of the common wall will be at a low valueduring shutdown of the fan. Control of the compressor and fan isobtained by a temperature control adapted to maintain a F. freezertemperature, for example.

A fan is also mounted within the fresh food space so as to circulate airthrough a duct or conduit located against the common wall dividing thetwo compartments. This forced circulation of air within the fresh foodcompartment will provide a high surface coefficient of heat transfer onthe fresh food space side of the dividing wall when this fan isoperated. The fresh food space fan is normally controlled by atemperature control so as to maintain about a 38 F. temperature in thefresh food space. However, its operation is modified so that, during theoff period of the compressor and therefore the off period of the fan inthe frozen food compartment, the fresh food space fan is forced tooperate to insure that the temperature of the surface of the dividingwall in the fresh food space will reach a temperature above 32 F.

The design of the system is such that the velocity of the air on eitherside of the dividing insulated wall, taken with the heat conductivitythrough this wall, results in the surface temperature on the fresh foodside of the dividing wall being above, but close to, 32 F when both fansand the compressor are operating. This surface will fall below 32 F.,then, only when the fan in the fresh food compartment is controlled andstopped by its temperature control while the compressor and freezer fanoperate. This surface will again warm rapidly to above 32 F. during acompressor off period since, at this time, the fresh food space fan willagain begin to operate to circulate 38 F. air against the dividing wallsurface. Because the dividing wall surface on the fresh food space sidewill be below the dewpoint of the fresh food air, any moisture presentin the air will condense on this wall and flow by gravity to aconveniently mounted drain tube to be carried out of the refrigeratorcabinet.

A refrigeration control system to control the aforementioned operationof the compressor and the two fans, and a defroster arrangement for thefrozen food space is also provided to carry out the principles of theinvention.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in front sectionalelevation which partially shows the refrigerator and the mechanicaloperating components of the refrigeration system for it;

FIG. 2 is a plan view in cross section of the apparatus of FIG. 1, takengenerally on line IlII of FIG. 1; and

FIG. 3 is a schematic diagram of the control system and its operativerelationship to the refrigeration system.

DESCRIPTION OF THE PREFERRED EMBODIMENT The structure and advantages ofthe instant invention will become more apparent as reference is made tothe drawings wherein a portion of a refrigerator 10 (FIGS. 1 and 2) isshown having a frozen food compartment 12 and a fresh food compartment14 disposed in a side-by-side relationship with an insulated dividingwall 16 disposed therebetw-een so that frozen food compartment 12 may berefrigerated to a lower temperature than the fresh food compartment 14.Cooling for both compartments is provided by an evaporator coil 18situated behind a rear wall 17 of the frozen food space 12 and locatedso that air circulating over its individual coils will provide a coolingeffect to the air in the frozen food compartment 12.

A fan 20 provides a forced airflow through this evaporator coil byreceiving air through an inlet 22 and discharging the air through anoutlet 24. The discharge 24 is in direct communication with a duct 26that is substantially the same width as the thickness of the evaporatorcoil 18 and extends towards the fresh food compartment 14 along the backside of the refrigerator along a portion of a rear wall 28 that formsone of the walls outlining the peripheries of the freezing compartment12 and between it and the rear wall 17. Duct 26 communicates with a duct30 disposed against dividing wall 16 and dimensioned to substantiallycover the full length and width of this wall. This duct is open at bothits upper and its lower ends to form exits 32 and 34 which discharge theair driven by the fan 20 both above and below the evaporator coil 18.The exits 32 and 34 extend for approximately two-thirds the depth of thefreezer compartment 12 and the duct 30 so as to distribute the airdriven by the fan 22 throughout the freezing space 12 forwardly of theevaporative coil 18, with a face 33 of dividing wall 16 receiving amajor cooling effect from the circulating air.

A second fan 36 is disposed in the fresh food compartment 14 to providea circulating flow ofair on a face 38 on the fresh food compartment sideof dividing wall 16. This fan is mounted on the wall 16 so as to bedisposed intermediate its height and width, with an inlet 40 for the airflowing inwardly here as directed by the fan 36 being provided atsubstantially this same location. A panel 42 provides a duct or conduit44 to receive the discharge from the fan 36, with this conduit beingformed substantially over the entire area of the dividing wall 16. Morespecifically, the wall 42 extends contiguous to the wall 16 for itsentire linear and lateral extent to thereby form the conduit 44 betweenit and the wall 16 so that air entering through fan entrance 40 isdriven by the fan 36 along and against the dividing wall 16 forsubstantially its entire length and width. A pair of discharges 46 and48 located, respectively, at the upper and lower ends of the duct 44permit the air circulated against the wall 16 to be discharged into thefresh food space 14, proper, so as to cool this space and any foodlocated therein.

The general operation of the refrigerator 10 will now be described.Evaporator coil 18 is controlled as to provide a temperature of, say F.within the freezer space 12 with the fan 20, when operating, providing arapid flow of air through conduit 30 thereby insuring a fairly high heattransfer coefficient at the boundary between this flow of cool air andthe face 33 of dividing wall 16. Refrigeration for the fresh food space14 is derived from the heat transfer through the dividing wall 16, withthe fan 36, when operating, providing a fairly high heat transfer rateat the boundary between the face 38 of dividing wall 16 and the flow ofair within the conduit 44 as propelled by the fan 36. Discharge exits32, 34 and 46, 48 ensure that both the freezer space 12 and fresh foodspace 14 receive a circulation of cooling air throughout eachcompartment. In the fresh food compartment 14 any moisture contained inthe air in this refrigerated space will tend to condense out on the face38 of the dividing wall 16 since this face is generally above 32 F butat a lower temperature than any of the other surfaces in thiscompartment. This condensate is permitted to drain down the dividingwall 16 to be collected at the bottom thereof for exit through acondensate drain 50.

Turning to FIG. 3, the control system for the air-conditioning systemwill now be detailed. A refrigerator control system 52 includes a lead54 extending from one side of an AC source 55 for electrical connectionto a thermostatic control 56 mounted within the fresh food compartmentof the refrigerator. This thermostatic control contains a switch 57which is placed in a closed, current-carrying condition when thetemperature within the fresh food storage space 14 exceeds 38, forexample. A lead 58 extends from the other side of the switch of thethermostatic control 56 to a winding 60 of a refrigerator fan 36 so thatthis fan is actuated when signaled by the closed thermostatic control56. A lead 62 extends from the opposite end of the winding 60 of the fan36 to be connected to a door operated switch 64 which is placed in anoncurrentcarrying condition whenever the door the the fresh foodcompartment 14 of the refrigerator cabinet is opened. To complete thecircuit for actuation of the refrigerator fan 36 by thermostatic control56, a lead 66 extends from the opposite side of door operated switch 64to the AC source 55, this lead, of course, being in electricalconnection with one of the contacts of the door operated switch 64. Bythe arrangement just described, a fresh food fan-operating circuit means68 is provided which will operate the fresh food compartment fan 36whenever the door to this compartment is closed and whenever thethermostat 56 signals that the temperature of this space is above, forexample, 38 F.

A defrost timer operated switch (to be described in greater detaillater) 70 also is connected to the lead 54 to be electrically connectedto a freezer thermostatic control 72 when the switch 70 is in its upperposition through a lead 71. The thermostatic control 72 is containedwithin the frozen food com partment l2 and is capable of closing againsta contact 76 or a contact 78 by means of a switch blade 74, with thecontact 76 closed representing the position that the freezerthermostatic control 72 assumes when the temperature in the freezercompartment is below or at its setting-With the switch blade 74 in thisposition, an electrical connection is formed between it and a lead 80that extends upwardly so as to be electrically connected with the lead58.

By the circuit arrangement just described, i.e., the defrost timeroperated switch 70, the lead 71, the switch blade 74 of the thermostaticcontrol 72, the contact 76 and the lead 80, an overriding circuit means82 is provided which ensures that the fresh food compartment fan 36 isoperating whenever the frozen food compartment thermostatic control 72is not signaling for operation of the evaporator coil 18 to providerefrigeration within the frozen food compartment 12. It is specificallypointed out that the fresh food compartment fan 36 will operate with theswitch blade 74 of thermostatic control 72 in the position related,completely independent of the temperature conditions imposed on therefrigerator fresh food compartment thermostatic control 56, since thedefrost timer operated switch 70, lead 71, thermostatic control 72 andlead 80 will provide a flow path for current through the winding 60 ofthe fresh food compartment fan 36,'parallel to the flow path throughthermostatic control 56.

A compressor operating and freezer fan operating circuit means 84 isalso provided. A lead 86 extends from and is an electrical connectionwith the contact 78 of the thermostatic control 72. This lead isextended to form a pair of branch leads 88 and 90 that provide foractuation of a compressor-driving electric motor 92, with this motordriving a compressor (not shown) for the refrigeration system. Bothleads 90 and 88 extend to and are in electrical connection with astarting relay 94 which includes a winding 96 attached to lead 90 and aswitch 98 which closes to be in electrical contact with lead 88 uponsufficient current flowing through the winding 96 to afford magneticattraction for it. Leads 100 and 102 extend, respectively, from theopposite contact of the switch 98 and from the opposite side of thewinding 96. Lead 100 is connected at its opposite end to the startingcoil 104 of the motor 92 and lead 102 is connected at its opposite endto the main winding 106 of the motor 92. The starter winding 104 and themain winding 106, as is conventionaLjoin together at a terminal 108opposite to their connections with the leads 100 and 102. A lead 110extends from the terminal 108 to a motor overload protector switch 112which takes the form of a bimetallic switch element 114 that willoperate to open the circuit to the motor 92 when the current and thetemperature of protector 112 have assumed set overload values for apredetermined period of time. A lead 116 extends from a contact of theoverload protector switch 112 for connection to the lead 66 that alsoforms a portion of the circuit means for actuation of the fresh foodspace fan 36.

It should be clear from the circuitry just described that electric motor92 will be actuated with the defrost timer operated switch 70 in itsupper position) upon switch blade 74 assuming an abutting position withcontact 78. This position is dictated by the temperature within thefreezer compartment, that is, at some temperature, for example, above 0will cause the thermostat 72 to move the switch blade 74 into contactwith contact 78. This energizes leads 88 and 90 and, because of the highcurrent surge through the winding 96, the switch 98 closes to providecurrent to the starting winding 104. After the motor 92 has assumed anactive operating condition (rotating), a reduced current supplied to themain winding 106 maintains operation and the reduced current flowthrough winding 96 permits contacts 98 to open thereby deenergizingstart winding 104. The overload protector 112 is in a currentcarryingcapacity unless overload conditions are reached to complete the circuitfor the flow of current through the leads 116 and 66 back to theopposite side of the AC source 55. Such circuitry may be characterizedas a compressor mot0ractuating circuit means 1 1 7.

A circuit means 118 for activation of the freezer compartment fan isalso provided. it includes a lead 120 that extends from and is anelectrical connection with the lead 86 and a winding 122 of the freezerfan 20. A lead 124 extends from the opposite side of the winding 122 forconnection to a door operated switch 126, this switch assuming a closedcurrentcarrying condition whenever the door to the frozen foodcompartment 12 is closed. A lead 128 extends from an opposite contact ofdoor-operated switch 126 so as to be electrically connected to the lead66 to provide a path flow for current to the other side of the AC source55. Thus, with the thermostat control switch 72 in a closed positionwith contact 78, not only is the electric motor 92 energized, but alsothe freezer fan 20 so that cooling provided by the evaporator coil 18 isimparted to a flow of air which is force-fed through the duct 30 by thefan 20.

Although defrosting of the fresh food compartment 14 is not requiredsince the combined functioning of the fans 20 and 36, as well as thethermal conductivity characteristics of the dividing wall 16, ensurethat the face 38 is, for most of the time, above the temperature of 32",a defrost arrangement is provided for the frozen food compartment 12.Its actuating circuit means 130 includes a contact blade 132 of thedefrost timer-operated switch 70 which is in electrical connection withone side of the AC source 55. This contact blade (in its lowernonillustrated position) is in electrical connection with a contact 133of the switch 70 of a defrost timer 134 which may be set on some timedelayed cycle such as 12 hours. A lead 136 is electrically connected tothe opposite contact 133 of the defrost timer 134 and extends to and isin electrical connection with a defrost thermostat 138, with thisthermostat controlling the temperature at which defrost heating isterminated for the evaporative cooling coil 18. A lead 140 extends fromthe defrost thermostat 138 for electrical connection with a defrostheater 142 which provides the heat for the defrost cycle. This circuitis completed by a lead 144 which extends from defrost heater 142 so asto be in electrical connection and current carrying capacity with lead66 that, as set out previously, returns to the other side of the ACsource 55 through the defrost timer-operated switch 70, the connectinglead 136, the defrost thermostat 138, defrost heater 142 and lead 144back into the other side of the AC source 55 through lead 66.

As is conventional, the defrost timer 134 operates to open the defrosttimer switch 70 relative to the lead 71 at preset intervals, say of 12hours duration, to open the circuit to the compressor and to close thecircuit to the defrost heater 142. This defrosting condition continuesfor approximately minutes with the defrost thermostat 138 openingsometime during this time period to thereby open the circuit to thedefrost heater 142. The timer motor (represented by a winding 146 inFIG. 3) remains energized for the rest of the 25- minute period throughthe circuit from it to lead 71 and thence to the main compressor winding106 to lead 66' and then back to the AC source 55. At the termination ofthe 25- minute period, the contact blade 132 is forced back to its upperposition to provide refrigeration for the system. The defrost thermostat138 recloses when the evaporator cooling coil is again at a preselectedcold temperature.

Although only a single embodiment of the invention has been shown anddescribed, it should be apparent to those skilled in the art thatmodifications can be made therein without the exercise of invention. Forexample, the system described could be easily utilized with arefrigerator having frozen food and fresh food compartments disposedvertically rather than side by side. The frozen food space fan and freshfood space fan could also be placed at different locations than thoseillustrated so long as a flow of air was provided by each fan whichmoved along the dividing wall between the fresh and frozen foodcompartments or the dividing wall on either side could be extended (bycorrugations or fins, for example) to provide the desired heat transferrequired. Additionally, a more sophisticated system could be utilizedthan the one disclosed wherein an extra. thermostat control could beprovided which would control and be sensitive to the coldest area on thesurface of the dividing wall and this thermostat could then disconnectthe freezer fan and force operation of the fresh food fan when suchtemperature was reached. Such an arrangement, of course, would ensurethat there were no unwanted frost accumulation on the surface of thedividing wall which was open to the fresh food compartment and even moreseverely limit moisture pickup from the food stored in the fresh foodcompartment.

What is claimed is:

1. A refrigerator including;

a. a frozen food compartment,

b. a fresh food compartment,

0. a common dividing wall disposed therebetween,

d. cooling means for said frozen food compartment including anevaporator and means for circulating chilled air from said evaporatoralong the frozen food compartment side of said dividing wall, e. controlmeans for controlling the cooling operation in said frozen foodcompartment in response to a demand for cooling in said frozen foodcompartment,

. means for circulating an independent flow of air in said fresh foodcompartment along the fresh food compartment side of said dividing wall,

g. control means for effecting said independent flow of air in saidfresh food compartment independent of the cooling operation in saidfrozen food space, and

h. control means for effecting said independent flow of air in saidfresh food compartment in accordance with the termination of the coolingoperation in said frozen food compartment in response to a satisfieddemand in said frozen food space and independent of the demand forcooling in said fresh food compartment.

. An air-conditioning system for a refrigerator comprising;

a frozen food compartment fan-operating circuit,

a fresh food compartment fan-operating circuit,

a thermostatic control means for actuating said frozen food compartmentfan-operating circuit for maintaining a desired temperature for saidfrozen food compartment,

d. said thermostatic control means also providing for energization ofsaid fresh food compartment fan-operating circuit,

e. said thermostatic control means providing for actuating of only oneof said fan-operating circuits at a time.

3. The combination set out in claim 2 wherein said thermostatic controlmeans takes the form of;

a. a switch blade,

b. a pair of contacts engageable by said switch blade, and

c. said switch blade being capable of contacting only one of saidcontacts at a time.

4. The combination set out in claim 3 wherein said frozen food fanoperating circuit includes;

a. fan means in series relationship to said thermostatic control means,and

b. a compressor electric motor means disposed in parallel circuitrelationship with said fan means.

5. The combination set out in claim 4 wherein;

a. a thermostatic control means is provided for a fresh foodcompartment, and

b. said thermostatic control means is disposed in parallel circuitrelationship with said first mentioned thermostatic control means.

6. The combination set out in claim 5 wherein;

a. said first mentioned thermostatic control means actuatcs saidcompressor electric motor means simultaneously with actuation of saidfrozen food compartment fanoperating circuit.

7. The combination set out in claim 6 wherein;

a. a defrost control circuit is provided for the frozen foodcompartment.

8. The combination set out in claim 1 wherein;

a. said control means for effecting said independent flow of aircomprises a thermostatic control provided in said fresh foodcompartment,

b. said thermostatic control actuating said air circulating means insaid fresh food compartment independent of said operation of said aircirculating means in said frozen food compartment.

1. A refrigerator including; a. a frozen food compartment, b. a freshfood compartment, c. a common dividing wall disposed therebetween, d.cooling means for said frozen food compartment including an evaporatorand means for circulating chilled air from said evaporator along thefrozen food compartment side of said divIding wall, e. control means forcontrolling the cooling operation in said frozen food compartment inresponse to a demand for cooling in said frozen food compartment, f.means for circulating an independent flow of air in said fresh foodcompartment along the fresh food compartment side of said dividing wall,g. control means for effecting said independent flow of air in saidfresh food compartment independent of the cooling operation in saidfrozen food space, and h. control means for effecting said independentflow of air in said fresh food compartment in accordance with thetermination of the cooling operation in said frozen food compartment inresponse to a satisfied demand in said frozen food space and independentof the demand for cooling in said fresh food compartment.
 2. Anair-conditioning system for a refrigerator comprising; a. a frozen foodcompartment fan-operating circuit, b. a fresh food compartmentfan-operating circuit, c. a thermostatic control means for actuatingsaid frozen food compartment fan-operating circuit for maintaining adesired temperature for said frozen food compartment, d. saidthermostatic control means also providing for energization of said freshfood compartment fan-operating circuit, e. said thermostatic controlmeans providing for actuating of only one of said fan-operating circuitsat a time.
 3. The combination set out in claim 2 wherein saidthermostatic control means takes the form of; a. a switch blade, b. apair of contacts engageable by said switch blade, and c. said switchblade being capable of contacting only one of said contacts at a time.4. The combination set out in claim 3 wherein said frozen food fanoperating circuit includes; a. fan means in series relationship to saidthermostatic control means, and b. a compressor electric motor meansdisposed in parallel circuit relationship with said fan means.
 5. Thecombination set out in claim 4 wherein; a. a thermostatic control meansis provided for a fresh food compartment, and b. said thermostaticcontrol means is disposed in parallel circuit relationship with saidfirst mentioned thermostatic control means.
 6. The combination set outin claim 5 wherein; a. said first mentioned thermostatic control meansactuates said compressor electric motor means simultaneously withactuation of said frozen food compartment fan-operating circuit.
 7. Thecombination set out in claim 6 wherein; a. a defrost control circuit isprovided for the frozen food compartment.
 8. The combination set out inclaim 1 wherein; a. said control means for effecting said independentflow of air comprises a thermostatic control provided in said fresh foodcompartment, b. said thermostatic control actuating said air circulatingmeans in said fresh food compartment independent of said operation ofsaid air circulating means in said frozen food compartment.